The art of using a “gobo”, which is a thin metal template disk with cutout patterns or etched glass, to project light patterns on surfaces, is well known. Electric light fixtures incorporating gobos to project onto vertical or horizontal surfaces of walls, floors, table-tops, etc. have been commercially available. In addition, U.S. Pat. No. 6,113,252 of Arlitt describes a variety of embodiments of architectural luminaires with this capability as well.
The prior art does not describe an inexpensive projector accessory using, as a light source, an existing recessed lighting fixture.